Safeguarding human health in the Anthropocene epoch: report of The Rockefeller Foundation–Lancet Commission on planetary health

Analytical methods for determination of mycotoxins: A review

Mycotoxins are toxic secondary metabolites produced by certain filamentous fungi (molds). These low molecular weight compounds (usually less than 1000 Daltons) are naturally occurring and practically unavoidable. They can enter our food chain either directly from plant-based food components contaminated with mycotoxins or by indirect contamination from the growth of toxigenic fungi on food. Mycotoxins can accumulate in maturing corn, cereals, soybeans, sorghum, peanuts, and other food and feed crops in the field and in grain during transportation. Consumption of mycotoxin-contaminated food or feed can cause acute or chronic toxicity in human and animals. In addition to concerns over adverse effects from direct consumption of mycotoxin-contaminated foods and feeds, there is also public health concern over the potential ingestion of animal-derived food products, such as meat, milk, or eggs, containing residues or metabolites of mycotoxins. Members of three fungal genera, Aspergillus, Fusarium, and Penicillium, are the major mycotoxin producers. While over 300 mycotoxins have been identified, six (aflatoxins, trichothecenes, zearalenone, fumonisins, ochratoxins, and patulin) are regularly found in food, posing unpredictable and ongoing food safety problems worldwide. This review summarizes the toxicity of the six mycotoxins, foods commonly contaminated by one or more of them, and the current methods for detection and analysis of these mycotoxins.

Occurrence, Toxicity, and Analysis of Major Mycotoxins in Food

Global food production must increase by 50% to meet the projected demand of the world’s population by 2050. Meeting this difficult challenge will be made even harder if climate change melts portions of the Himalayan glaciers to affect 25% of world cereal production in Asia by influencing water availability. Pest and disease management has played its role in doubling food production in the last 40 years, but pathogens still claim 10–16% of the global harvest. We consider the effect of climate change on the many complex biological interactions affecting pests and pathogen impacts and how they might be manipulated to mitigate these effects. Integrated solutions and international co-ordination in their implementation are considered essential. Providing a background on key constraints to food security, this overview uses fusarium head blight as a case study to illustrate key influences of climate change on production and quality of wheat, outlines key links between plant diseases, climate change and food security, and highlights key disease management issues to be addressed in improving food security in a changing climate.

/pdf/climate-change-plant-diseases-and-food-security-an-overview-3bhf3j81bn.pdf

Climate change, plant diseases and food security: an overview

Mycotoxin contamination of the feed supply chain: Implications for animal productivity and feed security

This paper examines the available information on the potential for climate-change impacts on mycotoxigenic fungi and mycotoxin contamination of food crops pre- and postharvest. It considers the effect of changes in temperature/water availability on mycotoxin contamination, especially incidences where aflatoxin B1 and ochratoxin A production has been influenced. The potential of using preharvest models to predict risk from deoxynivalenol (DON) in wheat, fumonisin B1 in maize and aflatoxins in maize and peanuts in different continents are considered in the context of potential for adaptation to include climate-change scenarios. Available information suggests that slightly elevated CO2 concentrations and interactions with temperature and water availability may stimulate growth of some mycotoxigenic species, especially under water stress. The accumulated knowledge on interacting conditions of water/temperature effects on optimum and boundary conditions for growth and mycotoxin production has been used to predict the effects that +3 and +5°C increases under water stress would have on growth/mycotoxin production by mycotoxigenic species. Various spatial scales, from toxin gene expression to regional approaches using geostatistics, are examined for their use in understanding the impact that climate change may have on food contamination in developing and developed countries. The potential for using an integrated systems approach to link gene expression data, phenotypic toxin production under different interacting abiotic conditions is discussed using Fusarium species and DON as examples. Such approaches may be beneficial for more accurate predictions of risk from mycotoxins on a regional basis and also the potential for new emerging toxin threats.

https://onlinelibrary.wiley.com/doi/pdf/10.1111/j.1365-3059.2010.02412.x

Possible climate-change effects on mycotoxin contamination of food crops pre- and postharvest

This review considers the available information on the potential impact of key environmental factors and their interactions on the molecular ecology, growth and aflatoxin production by Aspergillus flavus in vitro and in maize grain. The recent studies which have been carried out to examine the impact of water activity × temperature on aflatoxin biosynthesis and phenotypic aflatoxin production are examined. These have shown that there is a direct relationship between the relative expression of key regulatory and structural genes under different environmental conditions which correlate directly with aflatoxin B1 production. A model has been developed to integrate the relative expression of 10 biosynthetic genes in the pathway, growth and aflatoxin B1 (AFB1) production which was validated under elevated temperature and water stress conditions. The effect of interacting conditions of aw × temperature × elevated CO2 (2 × and 3 × existing levels) are detailed for the first time. This suggests that while such interacting environmental conditions have little effect on growth they do have a significant impact on aflatoxin biosynthetic gene expression (structural aflD and regulatory aflR genes) and can significantly stimulate the production of AFB1. While the individual factors alone have an impact, it is the combined effect of these three abiotic factors which have an impact on mycotoxin production. This approach provides data which is necessary to help predict the real impacts of climate change on mycotoxigenic fungi.

/pdf/effect-of-climate-change-on-aspergillus-flavus-and-aflatoxin-19efhk0udm.pdf

Effect of climate change on Aspergillus flavus and aflatoxin B1 production

An overview of ochratoxin A in beer and wine.

Climate change, food security and mycotoxins: Do we know enough?

The native mycobiota of five grape varieties grown in Spain has been studied. Four (Bobal, Tempranillo, Garnacha, and Monastrell) were red varieties and one (Moscatel) was white. The main fungal genera isolated were Alternaria, Cladosporium, and Aspergillus. The isolation frequency of Aspergillus spp. section Nigri in contaminated samples was 82%. Ochratoxin A (OTA) production was assessed using yeast extract-sucrose broth supplemented with 5% bee pollen. Cultures of 205 isolates from this section showed that 74.2% of Aspergillus carbonarius and 14.3% of Aspergillus tubingensis isolates produced OTA at levels ranging from 1.2 to 3,530 ng/ml and from 46.4 to 111.5 ng/ml, respectively. No Aspergillus niger isolate had the ability to produce this toxin under the conditions assayed. Identification of the A. niger aggregate isolates was based on PCR amplification of 5.8S rRNA genes and its two intergenic spacers, internal transcribed spacer 1 (ITS1) and ITS2, followed by digestion with restriction endonuclease RsaI of the PCR products. The restriction patterns were compared with those from strains of A. niger CECT 2807 and A. tubingensis CECT 20393, held at the Spanish Collection of Type Cultures. DNA sequencing of the ITS1-5.8S rRNA gene-ITS2 region of the OTA-producing isolates of A. tubingensis matched 99 to 100% with the nucleotide sequence of strain A. tubingensis CBS 643.92. OTA determination was accomplished by liquid chromatography with fluorescence detection. OTA confirmation was carried out by liquid chromatography coupled to ion trap mass spectrometry. The results showed that there are significant differences with regard to the isolation frequency of ochratoxinogenic fungi in the different grape varieties. These differences were uncorrelated to berry color. The ability of A. tubingensis to produce OTA and the influence of grape variety on the occurrence of OTA-producing fungi in grapes are described in this report for the first time.

Angel Medina

Papers

Possible climate-change effects on mycotoxin contamination of food crops pre- and postharvest

Effect of climate change on Aspergillus flavus and aflatoxin B1 production

An overview of ochratoxin A in beer and wine.

Climate change, food security and mycotoxins: Do we know enough?

Study of Spanish Grape Mycobiota and Ochratoxin A Production by Isolates of Aspergillus tubingensis and Other Members of Aspergillus Section Nigri